(* The Haskell Research Compiler *)
(*
 * Redistribution and use in source and binary forms, with or without modification, are permitted 
 * provided that the following conditions are met:
 * 1.   Redistributions of source code must retain the above copyright notice, this list of 
 * conditions and the following disclaimer.
 * 2.   Redistributions in binary form must reproduce the above copyright notice, this list of
 * conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *)


(* For when things go wrong *)

signature FAIL =
sig
    val assert : string * string * string * (unit -> bool) -> unit
                 (* struct, routine, failure msg, assert fn *)
    val fail : string * string * string -> 'a  (* struct, routine, msg *)
    val unimplemented : string * string * string -> 'a
                        (* struct, routine, what *)
end;

structure Fail :> FAIL =
struct

    fun fail (s, r, m) = Assert.fail (s ^ "." ^ r ^ ": " ^ m)
    fun assert (s, r, m, assert) =
        if assert () then
            ()
        else
            fail (s, r, m)
    fun unimplemented (s, r, w) = fail (s, r, w ^ " unimplemented")

end;
